Concord, N.C. ? Self-proclaimed sham Mark Martin vowed to leave racing at the top of his game. A late-season surge has put him there, back in the chase for that elusive NASCAR title.

But getting there has been a drain — emotionally, mentally, and maybe even physically.

That has made it all too easy for Martin to begin the phasing-out stage of his career. The 45-year-old racer will make 2005 his final year of full-time competition.

“One of the reasons for my stepping out at this time is because I was never really convinced, deep down inside, that I was all that good,” Martin said. “I’ve fooled a lot of people for a long, long time, and I don’t want to take any chance on getting caught up in something where everybody figures out that I was sham, and I really wasn’t as good as the results I got.”

Martin never was a sham at Lowe’s Motor Speedway, site of tonight’s UAW-GM Quality 500. The suburban Charlotte track is his favorite on the circuit, and he owns four wins here. The last one was in 2002, when he broke a 73-race drought by taking the Coca-Cola 600.

That victory resurrected Martin’s career, and pushed him to a second-place finish in the series standings. But last season he wound up 17th — the worst finish in his first 17 years as a full-time competitor.

And in a bittersweet twist, teammate Matt Kenseth won the championship. Of course Martin was happy for his protege, but it still stung just a bit. After all, Martin is famous for never having won a title — finishing second four times and third another four.

The hard luck seemed to follow Martin into this season, where he lingered around 15th in the Nextel Cup standings for most of the year. But his Roush Racing team turned it up over the summer, and Martin clawed his way into NASCAR’s new 10-race championship playoff system.

Getting there was what finally convinced Martin he’d had enough full-time racing.

Driver Mark Martin, left, chats with crew chief Pat Tryson. The two talked Thursday at Lowe's Motor Speedway in Concord, N.C. Martin is fifth in the Nextel Cup standings.

“Chasing for the Cup in 2004 has definitely been the most consuming season of my life,” Martin said. “No one can understand how important it has been for me to be a contender.”

But his run through the championship hasn’t been spectacular — save for a second-place finish at Dover three weeks ago — and he currently is fifth in the standings, 150 points behind leader Kurt Busch, another Roush teammate.

A victory tonight would help Martin get back into the chase, and it also would make him the biggest winner among active drivers at Lowe’s. But the championship is what he covets, and if owner Roush had just one wish it would be for Martin to win it.